A lot of people shoot with their thumb against the slide safety on a 1911. I think it's uncomfortable and I shoot with more of a traditional grip. My colt had wear marks at the slide safety from the previous owner from the aforementioned grip.

When gripping the 1911 with the thumbs foreward grip, your thumb can almost automatically ride on the thumbsafety.
The rason is, that when carrying cocked and locked, you position your thumb on the safety and when ready to shoot just need to press down.

Same thing the other way round. When you fired a shot to prevent accidental discharge, you just need to move your thumb a bit down, under the safety and engage it.
Also it prevents accidential engegement of the safety.

It is more comfortable doing this with the long safetylevers, but also works fine with the original ones.

Me too. My pre firing hand position is thumb on the slide safety and finger on the trigger guard or just above it. But, once I start firing I adjust to finger on the trigger and thumb on the grips. Incidentally it's the same way I fire any weapon with a safety mounted on the slide as well such as my beretta px4.

But you can slow down the slide, and that will result in malfunction. This is why oversized safeties are utilized in competition.

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I could make a list of a bunch of guns i have, or "have", or wish I had. Why would one feel compelled to provide that infornation freely? Do you feel the need to show off? Is it some immature game of oneupsmanship?

Hello PeteZ, I have shot the 1911 type guns, with my thumb on the safety, since attending a couple of training classes at Gunsite years ago. Gunsite taught this thumb placement. I have used this hold with both the factory and extended type safeties. It has worked for me in carrying and using 1911 type pistols, and the FN/Browning, in recreational matches, and carrying the 1911 full time in LE.

Back when I shot regularly in practical pistol matches, it was not uncommon to see 1911 shooters,who used some version of thumb under the safety grip, inadvertently push up the safety as the gun came down after recoil. Then, mad fumbling as they momentarily struggle to figure out why their 1911 pistol won't shoot. I am not a Black Ops Ninja "Operator" expert, but have carried the 1911 in the military (RVN), and then LE, for years. The thumb atop the safety technique seems a simple way to insure that the thumb safety is not accidentally engaged...ymmv